Loud fan, and battery doesn't last two hours

I have a MacBook Air that is a year old. Just starting today after I updated the software My fan is now very loud every time I use my computer, and gets hot. Also the battery dies within a hour or two. My diagnostics report came up with no problems, restarting my SMC didn't seem to help and my cpu % is normal other then a item that keeps popping up after its deleted (cpu 390%). Any suggestions what else to do?